Issued: 2:02 PM PST Monday, February 1, 2021
by Dennis D'Amico

Jump to: Weather Forecast I Precipitation I Snow Level I 5000' Temps I Ridgeline Winds I Extended Weather

Weather Synopsis

The quasi-stationary frontal boundary that has been draped west of the Cascade crest since Saturday evening is still with us this afternoon, like a house guest that doesn't know when it's time to move along. Snow levels have settled in the 4000-6000' range across the region this afternoon. 2 day precipitation totals have varied widely in this pattern; 5.40" at Mt Baker, 2.80" at Hurricane Ridge, 1.75" Crystal Mt, 0.75" Mission Ridge and generally less than 0.50" everywhere else. 

The parent surface low will finally head inland this evening with a secondary wave developing along the boundary in northern California. This should stretch the boundary with most of the precipitation focused on the north Cascades once again as it lifts NE late this evening.  A wind shift from S-SE to W-SW will take place around midnight behind the frontal boundary. Snow levels will slowly lower later tonight. 

Post-frontal showers will be with us tomorrow as the upper-level low drops south along the coast. Showers should fire up tomorrow afternoon as the air mass becomes more unstable in the afternoon and an upper level shortwave invigorates showers activity in the afternoon. Snow levels will hover in the 2000-3000' range tomorrow and skies will remain cloudy.  

The trailing upper level trough will dig along the Oregon Coast Tuesday night and head inland on Wednesday. This should rotate a swatch of light snow into the southern Washington Cascades, Olympics and Mt Hood Tuesday night through Wednesday morning with less snow further north and east. A drying trend will take place on Wednesday. Clouds will stick around on the west side of the Cascade crest with more sunshine along the east slopes with cool freezing levels and generally light winds. 

Weather Forecast

Olympics
West North
West Central
West South
Stevens Pass
Snoqualmie Pass
East North
East Central
East South
Mt. Hood
Use dropdown to select your zone
Monday Night Light to moderate rain and snow becoming light to occasionally moderate showers in the late evening.
Tuesday Cloudy with light to occasionally moderate rain and snow showers.
Monday Night Heavy rain and snow becoming light to moderate showers after midnight.
Tuesday Cloudy with light to occasionally moderate rain and snow showers.
Monday Night Moderate rain and snow becoming light to moderate showers after midnight.
Tuesday Cloudy with light to occasionally moderate rain and snow showers.
Monday Night Light to moderate rain and snow becoming light to moderate showers after midnight. Moderate to strong ridgeline winds.
Tuesday Cloudy with light to occasionally moderate rain and snow showers. Showers heaviest Paradise area. Moderate to strong ridgeline winds.
Monday Night Light rain and snow occasionally moderate in the late evening, then light showers after midnight. Light east winds at Pass level becoming westerly after midnight.
Tuesday Cloudy with light to occasionally moderate rain and snow showers. Light to moderate west winds at Pass level.
Monday Night Light rain and snow occasionally moderate in the late evening, then light showers after midnight. Light east winds at Pass level becoming westerly after midnight.
Tuesday Cloudy with light to occasionally moderate rain and snow showers. Light to moderate west winds at Pass level.
Monday Night Light to occasionally moderate rain or snow in the evening, then scattered light showers after midnight.
Tuesday Cloudy with light rain and snow showers.
Monday Night Light to occasionally moderate rain or snow in the evening, then scattered light showers after midnight.
Tuesday Cloudy with light rain and snow showers.
Monday Night Light to occasionally moderate rain or snow early in the evening, then scattered light showers after midnight.
Tuesday Cloudy with light rain and snow showers.
Monday Night Light to occasionally moderate rain or snow early in the evening, then scattered light showers after midnight.
Tuesday Cloudy with light to occasionally moderate rain and snow showers.

Issued: 2:02 PM PST Monday, February 1, 2021

Precipitation (in)

Monday Night Tuesday Tuesday Night Wednesday
4 pm - 4 am 4 am - 4 pm 4 pm - 4 am 4 am - 4 pm
Hurricane Ridge 0.25 - 0.50 0.25 LT 0.25 0
Mt Baker Ski Area 1.00 0.25 - 0.50 0.25 0
Mt. Loop - Barlow Pass 0.50 0.25 - 0.50 LT 0.25 0
Stevens Pass LT 0.25 0.25 LT 0.10 0
Snoqualmie Pass 0.25 0.25 - 0.50 LT 0.25 0
Crystal Mt 0.50 0.25 0.25 0
Paradise 0.50 0.50 - 0.75 0.25 - 0.50 0.75 -1.00
White Pass 0.25 0.25 0.25 LT 0.10
Washington Pass 0.25 LT 0.10 LT 0.10 LT 0.10
Mission Ridge LT 0.25 LT 0.10 LT 0.10 0
Salmon la Sac - Gallagher Head LT 0.25 LT 0.25 LT 0.25 0
Tieton River - Darland Mt. LT 0.25 LT 0.25 0.25 LT 0.10
Mt Hood Meadows LT 0.25 0.25 0.25 - 0.50 LT 0.10
Timberline 0.25 0.25 - 0.50 0.25 - 0.50 LT 0.25
Hurricane Ridge Precipitation (in)
Monday Night 0.25 - 0.50
Tuesday 0.25
Tuesday Night LT 0.25
Wednesday 0
Mt Baker Ski Area Precipitation (in)
Monday Night 1.00
Tuesday 0.25 - 0.50
Tuesday Night 0.25
Wednesday 0
Mt. Loop - Barlow Pass Precipitation (in)
Monday Night 0.50
Tuesday 0.25 - 0.50
Tuesday Night LT 0.25
Wednesday 0
Stevens Pass Precipitation (in)
Monday Night LT 0.25
Tuesday 0.25
Tuesday Night LT 0.10
Wednesday 0
Snoqualmie Pass Precipitation (in)
Monday Night 0.25
Tuesday 0.25 - 0.50
Tuesday Night LT 0.25
Wednesday 0
Crystal Mt Precipitation (in)
Monday Night 0.50
Tuesday 0.25
Tuesday Night 0.25
Wednesday 0
Paradise Precipitation (in)
Monday Night 0.50
Tuesday 0.50 - 0.75
Tuesday Night 0.25 - 0.50
Wednesday 0.75 -1.00
White Pass Precipitation (in)
Monday Night 0.25
Tuesday 0.25
Tuesday Night 0.25
Wednesday LT 0.10
Washington Pass Precipitation (in)
Monday Night 0.25
Tuesday LT 0.10
Tuesday Night LT 0.10
Wednesday LT 0.10
Mission Ridge Precipitation (in)
Monday Night LT 0.25
Tuesday LT 0.10
Tuesday Night LT 0.10
Wednesday 0
Salmon la Sac - Gallagher Head Precipitation (in)
Monday Night LT 0.25
Tuesday LT 0.25
Tuesday Night LT 0.25
Wednesday 0
Tieton River - Darland Mt. Precipitation (in)
Monday Night LT 0.25
Tuesday LT 0.25
Tuesday Night 0.25
Wednesday LT 0.10
Mt Hood Meadows Precipitation (in)
Monday Night LT 0.25
Tuesday 0.25
Tuesday Night 0.25 - 0.50
Wednesday LT 0.10
Timberline Precipitation (in)
Monday Night 0.25
Tuesday 0.25 - 0.50
Tuesday Night 0.25 - 0.50
Wednesday LT 0.25

Issued: 2:02 PM PST Monday, February 1, 2021

Snow Level (ft)

Monday Evening Monday Night Tuesday Morning Tuesday Afternoon Tuesday Evening Tuesday Night Wednesday Morning Wednesday Afternoon
Olympics 3500' 2500' 2000' 2500' 2000' 1500' 2000' 2000'
West North 3500' 2000' 2000' 2500' 1500' 1000' 1500' 1500'
West Central 4000' 3000' 2000' 2500' 1500' 1000' 1500' 1500'
West South 4500' 3000' 2000' 2500' 2000' 1500' 1500' 1500'
Stevens Pass 4000' 3000' 2000' 2500' 2000' 1000' 1500' 1500'
Snoqualmie Pass 4500' 3000' 2000' 2500' 2000' 1000' 1500' 1500'
East North 4000' 3500' 3000' 2500' 1000' 0 1500' 1500'
East Central 4500' 4000' 3000' 3000' 2000' 1000' 1500' 1500'
East South 4500' 4000' 3000' 3000' 2000' 1000' 1500' 1500'
Mt. Hood 5500' 4500' 3000' 3000' 2500' 2000' 2000' 2000'
Olympics Elevation
Monday Evening 3500'
Monday Night 2500'
Tuesday Morning 2000'
Tuesday Afternoon 2500'
Tuesday Evening 2000'
Tuesday Night 1500'
Wednesday Morning 2000'
Wednesday Afternoon 2000'
West North Elevation
Monday Evening 3500'
Monday Night 2000'
Tuesday Morning 2000'
Tuesday Afternoon 2500'
Tuesday Evening 1500'
Tuesday Night 1000'
Wednesday Morning 1500'
Wednesday Afternoon 1500'
West Central Elevation
Monday Evening 4000'
Monday Night 3000'
Tuesday Morning 2000'
Tuesday Afternoon 2500'
Tuesday Evening 1500'
Tuesday Night 1000'
Wednesday Morning 1500'
Wednesday Afternoon 1500'
West South Elevation
Monday Evening 4500'
Monday Night 3000'
Tuesday Morning 2000'
Tuesday Afternoon 2500'
Tuesday Evening 2000'
Tuesday Night 1500'
Wednesday Morning 1500'
Wednesday Afternoon 1500'
Stevens Pass Elevation
Monday Evening 4000'
Monday Night 3000'
Tuesday Morning 2000'
Tuesday Afternoon 2500'
Tuesday Evening 2000'
Tuesday Night 1000'
Wednesday Morning 1500'
Wednesday Afternoon 1500'
Snoqualmie Pass Elevation
Monday Evening 4500'
Monday Night 3000'
Tuesday Morning 2000'
Tuesday Afternoon 2500'
Tuesday Evening 2000'
Tuesday Night 1000'
Wednesday Morning 1500'
Wednesday Afternoon 1500'
East North Elevation
Monday Evening 4000'
Monday Night 3500'
Tuesday Morning 3000'
Tuesday Afternoon 2500'
Tuesday Evening 1000'
Tuesday Night 0'
Wednesday Morning 1500'
Wednesday Afternoon 1500'
East Central Elevation
Monday Evening 4500'
Monday Night 4000'
Tuesday Morning 3000'
Tuesday Afternoon 3000'
Tuesday Evening 2000'
Tuesday Night 1000'
Wednesday Morning 1500'
Wednesday Afternoon 1500'
East South Elevation
Monday Evening 4500'
Monday Night 4000'
Tuesday Morning 3000'
Tuesday Afternoon 3000'
Tuesday Evening 2000'
Tuesday Night 1000'
Wednesday Morning 1500'
Wednesday Afternoon 1500'
Mt. Hood Elevation
Monday Evening 5500'
Monday Night 4500'
Tuesday Morning 3000'
Tuesday Afternoon 3000'
Tuesday Evening 2500'
Tuesday Night 2000'
Wednesday Morning 2000'
Wednesday Afternoon 2000'

Issued: 2:02 PM PST Monday, February 1, 2021

5000' Temperatures (°F)

Monday Night Tuesday
Max / Min Max / Min
Olympics 28 / 20 24 / 19
West North 30 / 22 24 / 20
West Central 29 / 23 24 / 22
West South 32 / 26 25 / 23
Stevens Pass 31 / 25 27 / 23
Snoqualmie Pass 31 / 25 25 / 21
East North 31 / 23 27 / 20
East Central 33 / 24 27 / 22
East South 32 / 27 27 / 23
Mt. Hood 33 / 27 26 / 24
Olympics 5000' Temperature Forecast
(Max / Min)
Monday Night 28 / 20
Tuesday 24 / 19
West North 5000' Temperature Forecast
(Max / Min)
Monday Night 30 / 22
Tuesday 24 / 20
West Central 5000' Temperature Forecast
(Max / Min)
Monday Night 29 / 23
Tuesday 24 / 22
West South 5000' Temperature Forecast
(Max / Min)
Monday Night 32 / 26
Tuesday 25 / 23
Stevens Pass 5000' Temperature Forecast
(Max / Min)
Monday Night 31 / 25
Tuesday 27 / 23
Snoqualmie Pass 5000' Temperature Forecast
(Max / Min)
Monday Night 31 / 25
Tuesday 25 / 21
East North 5000' Temperature Forecast
(Max / Min)
Monday Night 31 / 23
Tuesday 27 / 20
East Central 5000' Temperature Forecast
(Max / Min)
Monday Night 33 / 24
Tuesday 27 / 22
East South 5000' Temperature Forecast
(Max / Min)
Monday Night 32 / 27
Tuesday 27 / 23
Mt. Hood 5000' Temperature Forecast
(Max / Min)
Monday Night 33 / 27
Tuesday 26 / 24

Issued: 2:02 PM PST Monday, February 1, 2021

Ridgeline Winds (mph)

Monday Evening Monday Night Tuesday Morning Tuesday Afternoon
Olympics SW 10-20 SW 5-15 SW 5-15 SW 5-15
West North S 15-25 SW 10-20 SW 5-15 SW 15-25
West Central S 15-25 SW 15-25 SW 10-20 SW 15-25
West South SSW 20-30 SW 10-20 SW 20-30 SW 20-30
Stevens Pass SE 10-20 WSW 10-20 SW 5-15 SW 10-20
Snoqualmie Pass SE 10-20 WSW 10-20 SW 10-20 SW 15-25
East North SSE 10-20 SW 15-25 SW 5-15 SW 15-25
East Central S 15-25 WSW 15-25 WSW 10-20 SW 20-30
East South SSW 10-20 SW 15-25 WSW 10-20 SW 15-25
Mt. Hood SW 15-25 SW 15-25 WSW 20-30 SW 20-30
Olympics Ridgeline Winds (mph)
Monday Evening SW 10-20
Monday Night SW 5-15
Tuesday Morning SW 5-15
Tuesday Afternoon SW 5-15
West North Ridgeline Winds (mph)
Monday Evening S 15-25
Monday Night SW 10-20
Tuesday Morning SW 5-15
Tuesday Afternoon SW 15-25
West Central Ridgeline Winds (mph)
Monday Evening S 15-25
Monday Night SW 15-25
Tuesday Morning SW 10-20
Tuesday Afternoon SW 15-25
West South Ridgeline Winds (mph)
Monday Evening SSW 20-30
Monday Night SW 10-20
Tuesday Morning SW 20-30
Tuesday Afternoon SW 20-30
Stevens Pass Ridgeline Winds (mph)
Monday Evening SE 10-20
Monday Night WSW 10-20
Tuesday Morning SW 5-15
Tuesday Afternoon SW 10-20
Snoqualmie Pass Ridgeline Winds (mph)
Monday Evening SE 10-20
Monday Night WSW 10-20
Tuesday Morning SW 10-20
Tuesday Afternoon SW 15-25
East North Ridgeline Winds (mph)
Monday Evening SSE 10-20
Monday Night SW 15-25
Tuesday Morning SW 5-15
Tuesday Afternoon SW 15-25
East Central Ridgeline Winds (mph)
Monday Evening S 15-25
Monday Night WSW 15-25
Tuesday Morning WSW 10-20
Tuesday Afternoon SW 20-30
East South Ridgeline Winds (mph)
Monday Evening SSW 10-20
Monday Night SW 15-25
Tuesday Morning WSW 10-20
Tuesday Afternoon SW 15-25
Mt. Hood Ridgeline Winds (mph)
Monday Evening SW 15-25
Monday Night SW 15-25
Tuesday Morning WSW 20-30
Tuesday Afternoon SW 20-30

Issued: 2:02 PM PST Monday, February 1, 2021

Extended Weather Synopsis

A pair of upper level disturbances will slide down late Wednesday night through Friday, bringing more precipitation for the west slopes of the Cascades in NW flow aloft.  Snow levels will slowly rise toward the end of the work week as warmer air works inland with a strong ridge building well offshore around 135W.  

Extended Snow Level (ft)

Wednesday Night Thursday Thursday Night Friday
West North 1000' 2000' 3000' 4000'
Snoqualmie Pass 1000' 2000' 3000' 4000'
Mt. Hood 2000' 3500' 3000' 5500'
West North Elevation
Wednesday Night 1000'
Thursday 2000'
Thursday Night 3000'
Friday 4000'
Snoqualmie Pass Elevation
Wednesday Night 1000'
Thursday 2000'
Thursday Night 3000'
Friday 4000'
Mt. Hood Elevation
Wednesday Night 2000'
Thursday 3500'
Thursday Night 3000'
Friday 5500'

Jump to: Weather Forecast I Precipitation I Snow Level I 5000' Temps I Ridgeline Winds I Extended Weather

Previous forecast from Feb 1, 2021

The NWAC program is administered by the USDA-Forest Service and operates from the National Weather Service Forecast Office in Seattle. NWAC services are made possible by important collaboration and support from a wide variety of federal, state and private cooperators.

The 5000’ temperature forecast does not imply a trend over the 12 hr period and only represents the max and min temperatures within a 12 hr period in the zone. The 6-hr snow level forecast, the forecast discussion, and weather forecast sections may add detail regarding temperature trends.

The snow level forecast represents the general snow level over a 6 hr time period. Freezing levels are forecast when precipitation is not expected.

*Easterly or offshore flow is highlighted with an asterisk when we expect relatively cool east winds in the major Cascade Passes. Easterly flow will often lead to temperature inversions and is a key variable for forecasting precipitation type in the Cascade Passes. Strong easterly flow events can affect terrain on a more regional scale.

Ridgeline winds are the average wind speed and direction over a 6 hr time period.

The wind forecast represents an elevation range instead of a single elevation slice. The elevation range overlaps with the near and above treeline elevation bands in the avalanche forecast and differs per zone.

Wind direction indicates the direction the wind originates or comes from on the 16-point compass rose.

Water Equivalent (WE) is the liquid water equivalent of all precipitation types; rain, snow, ice pellets, etc., forecast to the hundredth of an inch at specific locations. To use WE as a proxy for snowfall amounts, start with a snow to water ratio of 10:1 (10 inches of snow = 1 inch WE). Temperatures at or near freezing will generally have a lower ratio (heavy wet snow) and very cold temperatures can have a much higher ratio (dry fluffy snow).

The label LT, is shorthand for ‘less than’.